This is a program project proposal to support multidisciplinary cooperative research in parasitic infections/diseases including schistosomiasts, trichinosis, filariasis and giardiasis. Basic and clinical scientists from departments of Anatomy, Pathology, Pharmacology and Medicine will collaborate with the Division of Geographic Medicine at Case Western Reserve University to apply advanced biomedical technology to the study of these infections. Specific emphasis will be placed on an interdisciplinary approach to 1) the pathogenesis of disease; 2) modulation of pathology; 3) mechanisms and regulation of host resistance; 4) structural correlates of host-parasite interactions; and 5) the metabolism of antiparasitic drugs as it related to side reactions in the host, antiparasitic effects of the drugs and hepatosplenic schistosomiasis. The model selected for particularly intensive investigation is schistosomiasis, which has been extensively studied at Case Western Reserve University for 15 years. The proposed collaborative effort represents an extension of overlapping areas of interest already developed by the involved investigators. It also affords an opportunity for young investigators trained in other disciplines to be engaged in biomedical research related to parasitic infection. Training research associates is another important objective of this program. Many aspects of this proposal are closely linked to collaborative research overseas which is supported by other means; this should allow a constant exchange of ideas and data generated both in the laboratory and in the field. This theme has already been established and emphasized at Case Western Reserve University.